Control for starter pinion engaging mechanism



Jan. 15, 1957 H. H. WAGNER 2 7 8 CONTROL FOR STARTER PINION ENGAGINGMECHANISM Filed Dec. 30, 1954 2 Sheets-Sheet l INVENTOR. HAROLD/[WAGNERBY ATTORNEYS Jan. 15, 1957 2,777,328

CONTROL FOR STARTER PINION ENGAGING MECHANISM H. H. WAGNER 2Sheets-$heet 2 Filed Dec. 50 1954 INVENTOR. HAROLD H. WAGNER BY bar/1%.1111111 1 1 1Q A TORNEYS United States Patent fiice 2,777,328 PatentedJan. 15, 1957 CONTRDL FOR STARTER PINION ENGAGING MECHANISM Harold H.Wagner, Peoria, 111., assignor to Caterpillar Tractor Co,v Peoria, 111.,a corporation of California Application December 30, 1954, Serial No.478,600

4 claims. or. 74-6) This invention relates to the starting mechanism foran internal combustion engine, and more particularly to th starterpinion engaging mechanism therefor.

The invention is particularly adapted for use in connect'ion withstarting mechanisms of the type disclosed in Patent No. 2,481,783 toRobinson et al. for Starting Mechanism for Internal Combustion Engineswhich isued on September 13, 1949 and also of the type disclosedinPatent No. 2,621,532. to Robinson et al. for Starter PinionEngagingMechanism which issued on December 16, 1952.

The former patent discloses a starting engine mounted on the side of aprimary engine and a driving connection from the starting engineincluding a pinion gear adapted to mesh with a ring gear on the flywheelof the primary engine. gether with centrifu'gally actuated latchingmechanism for holding the pinion gear in engagement with the ring gearduring starting of the primary engine. The latter patent discloses animprovement to the control mechanism whereby none of the latchingmechanism extends beyond the end of the pinion. The present invention isconcerned with a single lever control and mechanism for engaging thepinion with the ring gear and engaging. the starting engine clutch.

The control mechanisms disclosed in the above identified patents utilizeone control lever to move the starter pinion into engagement with thering gear and a. separate control lever to engage the friction clutchassociated with the starting engine. This arrangementof control levershas been found to havev certain disadvantages. One such disadvantage isthat the controls must be actuated in a definite sequence to preventdamage to the pinion or the ring gear or both. The clutch brake shouldfirst be applied to stop any rotation of the pinion; secondly, the rpinion engaging control lever must be actuated to engage the pinion;thirdly,'the starting engine clutch must be engaged; and fonrthly, theclutch must be disengaged after the primary engine has started and thepinion has been It is, therefore, an object of the. present invention toprovide a single lever control mechanism for the starting engine clutch,as well as the mechanism for engaging the starting pinion gear with theflywheel ring gear, which will insure a sequence of operation of firstengaging the starting pinion before engagement of the starting engineclutch and will automatically disengage the starting engine clutch upondisengagement of the pinion. Another object of this invention is toprovide a combined mechanism for the sequential engaging of the starterpinion and the starting engine clutch, said mechanism being of compactdesign and enclosed within a housing to prevent any fouling ormalfunction which might occur in exteriorly mounted interconnected leverlinkages.

The control mechanism is disclosed, to-

Other objects and advantages of this. invention will be made apparent inthe following description wherein reference is made to the accompanyingdrawings.

In the drawings:

Fig. l is a fragmentary view in section through a portion of a startingengine and the primary engine showing in detail the clutch partsassociated with the starting engine flywheel, the driving mechanismbetween the starting engine and primary engine disclosing the pinionengaging mechanism, and the single control lever to effect sequentialengagement of both'the pinion and the starting engine clutch; and

Fig. 2 is an enlarged isometric view of the single control lever withparts broken away to illustrate the details of construction.

In Fig. l of the drawings, a part of a conventional internal combustionengine is illustrated as comprising a housing lil enclosing a flywheel11 having a ring gear 12 which may be formed integrally therewith. Theprimary engine carries a separate starting engine, only part of which isshown as comprising a flywheel 13 carried on a crankshaft, part of whichis shown at 14 and a housing 15 enclosing the flywheel. Power from thestarting engine is transmitted through a drive shaft 16 to a pinion gear17, which is adapted to be brought into engagement with the ring gear 12to crank the primary engine.

The drive shaft 16 is driven from the starting engine flywheel througha'conventional clutch comprising a series of clutch plates 18 havingsplined connections with the interior of a recess 19 provided in theflywheel 13 and a series of cooperating clutch plates '26 alternatelyarranged with the plates 18 and havingsplined connections with a drivenshaft 21. The clutch plates are adapted to be compressed betweenpressure plates 22 also having splined connections with shaft 21, whichis supported for rotation in bearings 23 and 24. carried in the startingengine. flywheel 13 and an extension 15a of the housing 15 respectively.The. clutch driven shaft 21 carries a cluster gear 25 splined to theshaft 21 and meshing; with a second gear 26 splined to the drive shaft16. The cluster gear 25 is adapted for axial movement on shaft 21 sothat either end of the gear may be selectively positioned to mesh. withthe mating end of gear 26 to effect a high or a low speed ratio betweenthe starting engine and the drive shaft 16. The gear 25 is shifted bymeans of 'a shifter fork 27 mounted on a conventional shift rail 28 andprovided with a well-known spring-loaded detent-type locking mechanism,generally indicated at 29, to resist axial movement of gear 25 While inmesh with gear 26. The drive shaft is supported for rotation in bearings3t} and 31 carried in an internal wall 32' of the housing'lS andtheextension 1511. respectively. The enclosure formed by wall 32 andextension 15a which contains the speed change gears and the drive shaft16 is adapted to contain lubricating oil for the lubrication of moving.parts, 'and is provided withwa seal 33 to prevent leakage-of oil.intothe adg'acent housing 10. i Engagement of the clutch to transmit thefrom the flywheel to the driven shaft is accomplished by compressing theclutch plates through a plurality of cam levers, only one of which isillustrated at 35 as supported for rocking movement about a pin 36carried in a spider 37 having a threaded connection with the peripheryof the driven shaft. The ends of the cam levers are received withinrearwardly converging recesses 38 provided in a collar 39 carried forsliding movement on the driven shaft so that axial movement of thecollar effects engagement or release of the clutch. The periphery of thesliding collar 39 is provided with a groove 40 for the reception of theinwardly extending ends of a yolce 41 secured to a d sleeve 42 extendinginto and supported for rotation in the housing 15.

The starter pinion engaging mechanism is very similar to that disclosedin Patent No. 2,621,532. This mechanism comprises. a drive shaft 16carrying the pinion 17 which is splined to the shaft and is adapted forsliding movement thereon to effect engagement or disengagement with thering gear 12. The pinion gear is normally urged toward its disengagedposition illustrated in broken lines in Fig. 1 by a spring 43 carried inan axial bore provided in the drive shaft. The spring bears against areduced section of the axial bore and a shoulder 44 formed on a controlrod 45 carried in the axial bore of shaft 16. A collar 46 formed on theend of the control rod is re ceived within an enlarged bore in thepinion gear and is retained by a shoulder at the end of the boreenlargement and an internal snap ring 47. The control rod is providedwith a thrust plate 50 (also see Fig. 2) which is contacted by a yoke 51secured to an engaging shaft 52 rotatably supported within andconcentric with the sleeve 42. As shown in Fig. 2, a control handle 53is secured to the rock shaft 52 and the handle is moved in a clockwisedirection to effect engagement of the pinion. Further movement in aclockwise direction will cause 2. lug 54, integral with the handle, tocontact an car 55 provided on the sleeve and turn the sleeve in aclockwise direction to effect engagement of the starting engine clutch.

During starting of the primary engine it is desirable that the piniongear remain in mesh with ring gear 12 until the primary engine isbrought up to sufficient speed to assure its continued operation. Alatching mechanism comprising a pair of pawls 56 biased by a spring 5611to engage in a peripheral groove 57 in the control rod 45 is providedfor this purpose. As soon as a predetermined rotational speed is reachedby the pinion 17, centrifugal force causes the pawls to swing outwardlyto release the control rod. The spring 43 then urges the control rod tothe right, as viewed in Fig. 1, which disengages the pinion from thering gear. As the control rod moves in this direction duringdisengagement, the thrust plate 50 bears on the yoke 51 to rotate theengaging rock shaft 52 in a counter-clockwise direction. The controlhandle 53 moving with rock shaft 52 contacts a second ear 58 extendingfrom sleeve 42 to rotate said sleeve in a counter-clockwise directionand disengage the starting engine clutch.

To insure that the pinion is not rotating before attempting to engage itwith the ring gear, the control handle may be moved in acounter-clockwise direction to fully disengage the clutch and to movethe clutch collar 39 into contact with a braking disc 59. The controlhandle is then rocked in a clockwise direction for the sequentialoperation of first engaging the pinion with the ring gear followed byengagement of the starting engine clutch. As described above, as soon asthe primary engine starts and a predetermined rotational speed isreached by the pinion 17, it is automatically disengaged; at the sametime, the starting engine clutch is disengaged to prevent any adherenceofthe clutch plates 18 and in the event that they had become heatedduring engagement.

I claim:

1. In a starting mechanism for an engine having a ring gear, a starterdriven pinion gear wherein the pinion gear is slidably supported on ahollow shaft for movement to and away from the ring gear, and a frictionclutch interposed between the starter and the pinion gear, control meansfor sequential operation of first, engaging the pinion gear with thering gear, and second, engagement of the friction clutch, said controlmeans comprising a rod slidable in the hollow shaft, a yoke engaging therod and secured to a rock shaft, a control lever extending from the rockshaft, said lever being provided with a projecting lug to contact an earextending from a sleeve surrounding said rock shaft and carrying a yoketo effect engagement of the clutch.

2. In a starting mechanism for an engine having a ring gear, a starterdriven pinion gear wherein the pinion gear is slidably supported on ahollow shaft for movement to and away from the ring gear, and a frictionclutch interposed between the starter and the pinion gear, control meansfor sequential operation of first, disengaging the pinion gear from thering gear, and second,

disengagement of the clutch, said control means comprising a springassociated with a control rod to urge the pinion out of engagement withthe ring gear upon release of latch means which hold the pinion inengagement until a predetermined rotational speed is reached, a yokeengaging the control rod, a rock shaft supporting said yoke, a leversecured to said rock shaft, said lever being provided with a projectinglug to contact an ear extending from a sleeve surrounding said rockshaft and carrying a yoke to eflect disengagement of the clutch.

3. In a starting mechanism for an engine having a ring gear and a pinionon a sliding shaft for engagement with the ring gear, and a transmissionshaft and clutch parallel to but spaced from the pinion shaft fordriving the pinion, means including a yoke on a rockable shaft to effectengagement of the pinion, means including a yoke on a second rockableshaft to effect engagement of the clutch, and a single lever to actuateboth said rockable shafts in sequence to insure engagement of the pinionwith the ring gear before engagement of the clutch.

4. In a starting mechanism for an engine having a ring gear and a pinionon a sliding shaft for engagement with the ring gear, and a transmissionshaft and clutch parallel to but spaced from the pinion shaft fordriving the pinion, means including a yoke on a rockable shaft disposedtransversely of the pinion and transmission shaft to effect engagementof the pinion, means including a yoke on a hollow rockable shaft whichembraces the first rockable shaft to effect engagement of the clutch, alever on the first rockable shaft to rock it and engage the pinion, anda part on said lever engageable with a part on the hollow rockable shaftto rock it and cause engagement of the clutch only after the pinion isengaged.

References Cited in the file of this patent UNITED STATES PATENTS2,621,532 Robinson et al. Dec. 16, 1952 FOREIGN PATENTS 656,523 GreatBritain Aug. 22, 1951 891,685 France Dec. 17, 1943

